1. Field of the Invention
This invention relates to a method of increasing the tensile, flexural and compressive strengths and the EMI/RF/Microwave and radioactive isotope shielding of concrete, cement, gypsum or other pozzolan (alumina siliceous) such as fly ash using electroplated nickel oxide or copper coated stainless steel fibers, hydroxypropylcellulose, ethoxylated methylglucoside, petroleum coke powder or graphite and silica fume and non-radioactive alkali metals such as holmium and natural zeolites such as Clinoptilolite as radioactive trapping agents.
2. Discussion of the Related Art
Cement is a widely used building material, but it lacks the ability to shield electromagnetic radiation. As the environment is increasingly sensitive to electronic pollution, the ability of a building to shield electromagnetic radiation is of increasing importance.
There has been a strong demand of late for high-quality and lightweight radioactive isotope shielded building materials such as wall coverings and wallboard.
Stainless steel fibers reinforced concrete (SSRC), a well dispersed mixture of either short or chopped continuous or non-continuous fiber in cement in the range of 0.90 vol. % has been known since the 1970s. SSRC has many outstanding mechanical characteristics which are unsurpassed by conventional reinforced concretes particularly, chemical stability towards strong alkaline environment and long term durability of mechanical strength are a few essential features in the development of SSRC.
Fly ash can be substituted for cement in concrete mixes for global construction of infrastructures saving energy, disposing of waste products, protecting the environment against global warming emissions, improving the quality of concrete and reducing cost. Ultra fine fly ash can be added to silica fume to enhance the strength of concrete.
3. Statement of Need
There is a need for protecting reinforcing steel adding to the longevity of concrete structures by preventing the penetration of waterborne contaminants and chloride-laden liquids that cause the corrosion of reinforcing steel.
There is a need for increased bonding strength and contact resistivity between cement and structural steel or steel fibers.
Because of the developments in electronics technology, there is a need for EMI/RF/Microwave Interference shielding of building materials e.g. gypsum wallboard and concrete particularly in underground vaults containing power transformers and other electronics that are relevant to electric power and telecommunications and for deterring electromagnetic forms of spying.
There is a need for an environmentally friendly way to recycle ashes produced from the industrial combustion of coal and petroleum and the minerals and metals contained therein e.g. selenium, vanadium, nickel and holmium.
There is definitely a need for a way to trap radioactive nuclear fission products (isotopes) e.g. 137Cs and 90Sr accidentally or intentionally released into the environment.